Can Levothyroxine alter kidney function?

[Jmthomas55]

Hi I was diagnosed with under active thyroid in 2014.been on levothyroxine since then.Just had some bloods done my renal function was below what it should be.Looking back through my levels over last 10 years it appears never been normal range apart from prior to me taking Levothyroxine.Anyone else had similar issue. Gp has only just noticed

[TiggerMe Ambassador]

Welcome aboard

Usually kidney function improves when on the right dose of thyroid hormones... How are you feeling? Have you any recent blood test results you can share, with ranges as they vary between labs

Ideally TSH, fT3 and fT4

[Jmthomas55 in reply to TiggerMe]

Thyroid levels are within normal range,I feel fine blood tests show abnormal gfr and creatinine,but when you look back they have been out of range since I started levothyroxine 10 years ago.Albiumin in urine so have to repeat that to.Thanks for responding

[TiggerMe Ambassador in reply to Jmthomas55]

I'm afraid 'normal' doesn't do it for us the ranges are far too wide, we aim for optimal which can be quite different, so it sounds like you have been under-replaced since the start which isn't unusual 🫤

Like I say, show us some past results also if you have any for folate, ferritin, B12 and Vit D

[Jmthomas55 in reply to TiggerMe]

My dose 75 one day 50 the next

Vit D level60 on daily supplement

B12 474

Ferritin 91

Follate 10.28

Tsh now 1 .43

was 23 at diagnosis then has been anything from 0.05 to 4.45 fluctuates was very sensitive to thyroxine at start as put on too high a level.

Iam interested to know if anyone has had abnormal renal function when taking thyroxine and if there's a link

[SlowDragon Administrator in reply to Jmthomas55]

That’s a very very low dose levothyroxine

Are you male or female

Approx weight

Recommended that all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

is this how you do your tests?

How long also were these vitamins tested

Are you in U.K.?

Vitamin D - if units are nmol …..60nmol is too low

B12, folate also too low

What vitamin supplements are you taking

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

Post all about what time of day to test

healthunlocked.com/thyroidu...

Testing options and includes money off codes for private testing

thyroiduk.org/testing/

Medichecks Thyroid plus BOTH TPO and TG antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes BOTH TPO and TG antibodies, cortisol and vitamins

bluehorizonbloodtests.co.uk...

Medichecks and BH also offer private blood draw at clinic near you, or private nurse to your own home…..for an extra fee

Only do private testing early Monday or Tuesday morning.

Tips on how to do DIY finger prick test

support.medichecks.com/hc/e...

[TiggerMe Ambassador in reply to Jmthomas55]

So no results for freeT4 and freeT3 which are important to see where your levels are and how well you are converting to the active fT3... your TSH is a little high suggesting your current dose is too low

SlowDragon has been really thorough with her replies which might take you a rainy Sunday to work through so I shall just add that it is low fT3 that effects kidney function so as it certainly looks like you would be better on a 75/100 dose for your size and hopefully that would give you system enough fT3 and improve your kidney function.

I myself had very poor kidney function on levo until I added T3 77 to <90 (80 pre levo)

also my creatinine levels dropped from 76 to 56 (70 pre levo)

I'm a poor converter hence the need for a combination of T3 & T4, which maybe the case for you, it isn't Levo that causes kidney issues it's the lack of fT3 possibly due to low dose Levo or lack of conversion

Hope that helps

[SlowDragon Administrator]

Even if we frequently start on only 50mcg, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or somewhere near full replacement dose (typically 1.6mcg levothyroxine per kilo of your weight per day)

Most important results are ALWAYS Ft3 followed by Ft4 …..not just TSH

cks.nice.org.uk/topics/hypo...

bnf.nice.org.uk/drugs/levot...

nhs.uk/medicines/levothyrox...

Adults usually start with a dose between 50 micrograms and 100 micrograms taken once a day. This may be increased gradually over a few weeks to between 100 micrograms and 200 micrograms taken once a day.

Some people need a bit less than guidelines, some a bit more

TSH should be under 2 as an absolute maximum when on levothyroxine

gponline.com/endocrinology-...

Graph showing median TSH in healthy population is 1-1.5

web.archive.org/web/2004060...

Comprehensive list of references for needing LOW TSH on levothyroxine

healthunlocked.com/thyroidu....

onlinelibrary.wiley.com/doi...

If symptoms of hypothyroidism persist despite normalisation of TSH, the dose of levothyroxine can be titrated further to place the TSH in the lower part of the reference range or even slightly below (i.e., TSH: 0.1–2.0 mU/L), but avoiding TSH < 0.1 mU/L. Use of alternate day dosing of different levothyroxine strengths may be needed to achieve this (e.g., 100 mcg for 4 days; 125 mcg for 3 days weekly).

sciencedirect.com/science/a...

The optimal daily dose in overt hypothyroidism is 1·5–1·8 μg per kg of bodyweight, rounded to the nearest 25 μg.

[SlowDragon Administrator]

Low thyroid levels, especially low Ft3 strongly linked to low GFR

pmc.ncbi.nlm.nih.gov/articl...

The GFR is reversibly reduced (by about 40%) in more than 55% of adults with hypothyroidism[40]

Hypothyroidism results in a reversible elevation in serum creatinine due to the reduction in GFR as well as possible myopathy and rhabdomyolysis. There is a reduction in serum cystatin C levels in hypothyroidism due to reduced production, consequent to reduced cellular metabolism.[30] Both these changes are reversible with treatment of hypothyroidism. Hypothyroidism also results in increased glomerular capillary permeability to proteins.[47] The consequent proteinuria often precedes the reduction in GFR in hypothyroidism.[48]

[Jmthomas55 in reply to SlowDragon]

Iam female weigh 55kg I couldn't tolerate higher dose started on 50 went up to 100 didn't suit me ended up overactive and under weight this current dose does suits me.Its taken ages to find what works for meInterested to read this re gfr and thyroid,Gp has only just noticed my renal function below range.

[SlowDragon Administrator in reply to Jmthomas55]

started on 50 went up to 100 didn't suit me ended up overactive

That was far too large an increase in one go …..but now probably on too low a dose

Suggest you work on improving low vitamin levels

Retest thyroid and vitamin levels again in further 8 weeks

Testing thyroid as outlined above

guidelines suggest somewhere around 88mcg daily likely necessary

Which brand of levothyroxine are you taking

Do you always get same brand at each prescription

[SlowDragon Administrator]

GP will often only prescribe to bring vitamin D levels to 50nmol.

Some areas will prescribe to bring levels to 75nmol or even 80nmol

leedsformulary.nhs.uk/docs/...

GP should advise on self supplementing if over 50nmol, but under 75nmol (but they rarely do)

mm.wirral.nhs.uk/document_u...

But improving to around 80nmol or 100nmol by self supplementing may be better

pubmed.ncbi.nlm.nih.gov/218...

vitamindsociety.org/pdf/Vit...

Once you Improve level, very likely you will need on going maintenance dose to keep it there.

Test twice yearly when supplementing

Can test via NHS private testing service

vitamindtest.org.uk

Vitamin D mouth spray by Better You is very effective as it avoids poor gut function.

There’s a version made that also contains vitamin K2 Mk7.

One spray = 1000iu

amazon.co.uk/BetterYou-Dlux...

It’s trial and error what dose we need, with thyroid issues we frequently need higher dose than average

Vitamin D may prevent Autoimmune disease

newscientist.com/article/23...

Web links about taking important cofactors - magnesium and Vit K2-MK7

Magnesium best taken in the afternoon or evening, but must be four hours away from levothyroxine

betterbones.com/bone-nutrit...

medicalnewstoday.com/articl...

livescience.com/61866-magne...

sciencedaily.com/releases/2...

Recipe ideas

bbc.co.uk/food/articles/mag...

Interesting article by Dr Malcolm Kendrick on magnesium

drmalcolmkendrick.org/categ...

Vitamin K2 mk7

betterbones.com/bone-nutrit...

healthline.com/nutrition/vi...

[SlowDragon Administrator]

only add/change one vitamin supplement at a time

Wait 10-14 days to assess before adding another

With serum B12 result below 500, (Or active B12 below 70) recommended to be taking a separate B12 supplement

A week later add a separate vitamin B Complex 

Then once your serum B12 is over 500 (or Active B12 level has reached 70), you may be able to reduce then stop the B12 and just carry on with the B Complex.

If Vegetarian or vegan likely to need ongoing separate B12 few times a week

Highly effective B12 drops

natureprovides.com/products...

Or

B12 sublingual lozenges

uk.iherb.com/pr/jarrow-form...

cytoplan.co.uk/shop-by-prod...

In-depth article on different forms of B12

perniciousanemia.org/b12/fo...

B12 range in U.K. is too wide

Interesting that in this research B12 below 400 is considered inadequate

healthunlocked.com/thyroidu...

perniciousanemia.org/b12/le...

And why aiming to keep B12 over 500 recommended

perniciousanemia.org/b12/le...

Great reply by @humanbean on B12 here

healthunlocked.com/thyroidu...

Low folate

supplementing a good quality daily vitamin B complex, one with folate in (not folic acid)

This can help keep all B vitamins in balance and will help improve B12 levels too

Difference between folate and folic acid

healthline.com/nutrition/fo...

Many Hashimoto’s patients have MTHFR gene variation and can have trouble processing folic acid supplements

thyroidpharmacist.com/artic...

B vitamins best taken after breakfast

Igennus B complex popular option. Nice small tablets. Most people only find they need one per day. But a few people find it’s not high enough dose and may need separate methyl folate couple times a week

Post discussing different B complex

healthunlocked.com/thyroidu...

Thorne Basic B recommended vitamin B complex that contains folate, but they are large capsules. (You can tip powder out if can’t swallow capsule) Thorne can be difficult to find at reasonable price, should be around £20-£25. iherb.com often have in stock. Or try ebay

IMPORTANT......If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 5-7 days before ALL BLOOD TESTS , as biotin can falsely affect test results

endo.confex.com/endo/2016en...

endocrinenews.endocrine.org...

In week before blood test, when you stop vitamin B complex, you might want to consider taking a separate folate supplement (eg Jarrow methyl folate 400mcg) and continue separate B12

Post discussing how biotin can affect test results

healthunlocked.com/thyroidu...

helvella.blogspot.com/p/hel...